US 9,758,630 B2 · Assignee: TEIJIN LIMITED · Inventors: Kon; Tatsuichirou et al.
Sheet 1 of 7 from the published document. All sheets in the USPTO PDF
The present invention realizes a polymer substrate with hard coating layer comprising a high level of environmental resistance and a high level of abrasion resistance. A polymer substrate with hard coating layer is provided that comprises a polymer substrate ( 60 ) having a thickness of 1 mm to 20 mm and a hard coating layer ( 70,80 ) on the surface thereof. Here, in this polymer substrate with hard coating layer, the hard coating layer ( 70,80 ) is laminated on the surface of the polymer substrate, contains as a main component thereof a hydrolysis-condensation product of an organic silicon compound, has a thickness of 0.1 μm to 20 μm, makes direct contact with a cured underlayer on the opposite side of the polymer substrate, is formed from an organic silicon compound by PE-CVD, and satisfies all of the following requirements (a) to (c): (a) film thickness of the silicon oxide layer is within the range of 3.5 μm to 9.0 μm, (b) maximum indentation depth of the surface of the silicon oxide layer as determined by measuring nanoindentation under conditions of a maximum load of 1 mN is 150 nm or less, and (c) the value of critical compression ratio K of the silicon oxide layer, as defined by formula (1) in a 3-point bending test of the polymer substrate with hard coating layer that imparts indentation displacement in which the surface laminated with the silicon oxide layer becomes concave, is 0.975 or less.
For example, since resin molding materials having high transparency such as polycarbonate resin or acrylic resin have superior light weight, impact resistance, processability, integration ability with surrounding components and design properties in comparison with inorganic glass, they are widely used in place of organic glass in various types of applications in order to take advantage of these merits. However, since these resins are inferior to inorganic glass in terms of surface abrasion resistance and hardness, there are many cases in which they are used in the form of polymer substrates provided with a hard coating layer in which a polymer substrate is laminated with a hard coating layer for preventing damage to the polymer substrate. In the case of polymer substrates having a hard coating layer used in automobile window materials in particular (typically referred to as resin glazing
1 of 7 drawing sheets so far from the published document, cropped to the drawing. Every sheet is in the USPTO PDF.
What the patent claimed, word for word. All of it is now free to use.
The present invention relates to a polymer substrate having a hard coating layer and a method for producing that polymer substrate. More particularly, the present invention relates to a polymer substrate having a hard coating layer, which demonstrates superior abrasion resistance and can be used for a long period of time even in a harsh usage environment, and a Method for producing that polymer substrate. This polymer substrate having a hard coating layer can be used, for example, automobile window materials, construction members or surface protective plates of solar cells.
For example, since resin molding materials having high transparency such as polycarbonate resin or acrylic resin have superior light weight, impact resistance, processability, integration ability with surrounding components and design properties in comparison with inorganic glass, they are widely used in place of organic glass in various types of applications in order to take advantage of these merits.
However, since these resins are inferior to inorganic glass in terms of surface abrasion resistance and hardness, there are many cases in which they are used in the form of polymer substrates provided with a hard coating layer in which a polymer substrate is laminated with a hard coating layer for preventing damage to the polymer substrate.
In the case of polymer substrates having a hard coating layer used in automobile window materials in particular (typically referred to as resin glazing materials), a level of abrasion resistance comparable to that of inorganic glass is required to ensure mechanical strength required for use as a window material as well as visibility in terms of driving safety, while environmental performance is required so as to withstand outdoor exposure for long periods of time. With respect to environmental performance, it is necessary for these polymer substrates to demonstrate performance capable of passing various types of tests in anticipation of direct contact with moisture including inclement weather, use under both high humidity and dry conditions, use under both high temperature and low temperature conditions and exposure to high levels of ultraviolet rays. The previously proposed products can be said to be inadequate for use as resin glazing materials capable of stably realizing all of these required performance levels.
With respect to the abrasion resistance of inorganic glass and the like, when referring to standards such as the FMVSS205 safety standard applied in the U.S. or the ECE R43 safety standard applied in Europe, the required level of abrasion resistance with respect to windows used at sites requiring visibility during driving is defined as an increase in haze value (ΔH) of less than 2% or 2% or less as determined with a Taber abrasion test carried out for 1000 revolutions as defined in ASTM D1044.
Although polymer substrates having a hard coating layer (see, for example, Patent Documents 1, 2 and 3), obtained by depositing an organic silicon-based oxide polymer on a resin substrate by plasma-enhanced chemical vapor deposition (PE-CVD) using an organic silicon compound (such as organosiloxane, organosilane or silazane) for the raw material, have been proposed for use as resin glazing materials for applications requiring both high abrasion resistance and outdoor weather resistance in this manner, typically in the case of providing a hard coating layer having high hardness formed by PE-CVD on an outermost surface, due to the generation of considerable interface stress between the high hardness hard coating layer and the underlayer on which that layer is laminated, it becomes difficult to ensure durability and reliability of the resulting hard coating layer. There are also many cases in which resistance to a boiling water test, which is an accelerated test relating to direct contact with moisture in the usage environment and long-term standing in high-humidity, high-temperature environment (to be referred to as boiling water resistance), as well as resistance to a high-temperature endurance test, which is an accelerated test relating to temperature change in an usage environment (to be referred to as heat resistance), are inadequate, frequently resulting in the observation of defective adhesion of the high hardness hard coating layer as well as other defects such as peeling phenomena or crack formation.
For example, the aforementioned Patent Document 1 proposes a plastic laminate obtained by sequentially laminating an acrylic resin heat-cured film, an organosiloxane-based resin heat-cured film, and PE-CVD film using an organic silicon compound as raw material on at least one side of a plastic substrate, wherein the PE-CVD film is composed of a gradient zone, in which the abundance ratio of oxygen atoms to silicon atoms (O/Si ratio) increases gradually from the interface with the heat-cured film of the aforementioned organosiloxane-based resin, and a subsequent flat zone, in which the aforementioned ratio is nearly constant, and Examples 1 and 2 therein disclose laminates that realize Taber abrasion resistance performance of 2.0% or less, which is an object of that invention, boiling water resistance as determined by a boiling water immersion test of 2 hours, and heat resistance of 1000 hours at 110° C.
Although these exemplified references were carried out by the present applicants, with respect to the method used to evaluate boiling water resistance, several problems were determined to occur during the course of examinations conducted by the present applicants after the exemplified patent documents were filed. Namely, although the duration of immersion in boiling water is indicated as being 2 hours, it was determined that making the duration of immersion in boiling water to be at least 3 hours and preferably 4 hours or more is preferable in terms of adequately ensuring long-term reliability such as water resistance or moisture resistance. In addition, with respect to the method used to evaluate an adhesion test after immersing in boiling water, it was determined that simply evaluating immediately after testing using the crosscut tape test is inadequate, and that it is necessary to evaluate and confirm results at least 7 days after carrying out the test. This is because it was determined that, since there are many cases in which internal stress (and frequently compressive force) generated during layer formation remains in the silicon oxide layer formed by PE-CVD, and due to the action thereof, there are cases observed in which layer separation occurs over time.
On the basis of these findings, it was decided to carry out evaluation of adhesion in the boiling water test of the present invention according to the procedure described below.
Namely, an adhesion test is carried out in accordance with a crosscut tape test in compliance with JIS K5400 after immersing a polymer substrate having a hard coating layer in boiling water at 100° C., removing the polymer substrate from the boiling water after retaining in the boiling water for 3 hours, removing any adhered moisture, and finally allowing to stand in a room temperature environment for 2 hours. The crosscut tape test is carried out by forming 10×10 squares cut out at 1 mm intervals with a cutter knife in the form of a grid followed by affixing and adhering tape having a prescribed adhesive force (such as Nichiban Cellophane Tape™) and then peeling off the tape. The result for adhesion immediately after carrying out the crosscut tape test (state in which the layer is peeled or separated from the surface) was designated as the “initial result”, while the result obtained after the passage of 7 days after carrying out the crosscut tape test was designated as the “elapsed result”, and adhesive performance and the reliability thereof were judged to be favorable only in the case not only the “initial result”, but also the “elapsed result” were favorable.
According to this evaluation method, when boiling water resistance of the laminate of the aforementioned Patent Document 1 was reevaluated, although the “initial result” was favorable (100/100), according to the “elapsed result”, separation of the PE-CVD layer laminated according to the PE-CVD method occurred at sites where crosscuts were made. Namely, the result of evaluation in the case of Example 1 was 70/100 (layer separation occurred in 30 of the 100 squares), and the result of evaluation in the case of Example 2 was 0/100 (layer separation occurred in all 100 squares), with satisfactory results being unable to be obtained for both examples, thereby resulting in a need to improve performance.
In addition, in the aforementioned Patent Document 2, a laminate is proposed that has a plurality of coating layers comprising an outermost layer (I), obtained by plasma polymerization of an organic silicon compound, a lower layer (II), having a silicone coating composition containing a composite oxide fine particle dispersion, a silicone resin, a curing catalyst and a solvent, and a lower layer (III) consisting of an arbitrary acrylic resin, on an organic resin substrate, and in Examples 2, 4, 5 and 7, laminates are disclosed that have Taber abrasion resistance performance of 2.0% or less, which is an object of that invention. In addition, a correlation between individual properties of each layer that composes the laminates and performance is also disclosed.
However, in these examples, the haze values of the laminates are high at 2.7% to 3.0%, thereby resulting in the problem of images transmitted through the laminates being unclear, and since this makes their use in applications requiring visibility difficult, an object of present applicants in the form of a polymer substrate having a hard coating layer is not realized. Moreover, in these examples, although results for water resistance performance (using test conditions consisting of 3 days at 65° C.) and an accelerated weather resistance test are disclosed, there is no disclosure of boiling water resistance performance or heat resistance performance, and thus the object of the present applications in the form of a polymer substrate having a hard coating layer and a high level of weather resistance performance cannot be said to be realized.
In addition, in the aforementioned Patent Document 3, a multilayer product is proposed that is composed of a base material, a first layer obtained with a partial condensate of organosiloxane, and a second layer containing plasma-polymerized organic silicon and deposited at a power level of 10.sup.6 J/Kg to 10.sup.6 J/Kg in the presence of excess oxygen, results are disclosed in Example 2 indicating favorable appearance after an outdoor exposure test conducted for 1 year in Florida, U.S.A. (absence of microcracks) and favorable adhesion, and results indicating favorable appearance after an accelerated xenon weather resistance test at a cumulative radiation level of 6875 KJ/m.sup.2 (absence of microcracks) and favorable adhesion are disclosed in Examples 4 and 5.
However, in these examples, although the results of an accelerated weather resistance test are disclosed, there is no disclosure of boiling water resistance performance or heat resistance performance, and an object of the present applicants in the form of a polymer substrate having a hard coating layer and a high level of weather resistance performance cannot be said to be realized. PRIOR ART DOCUMENTS Patent Documents
Patent Document 1: Japanese Unexamined Patent Publication No. 2010-253683
Patent Document 2: Japanese Unexamined Patent Publication No. 2012-224077
Patent Document 3: Japanese Unexamined Patent Publication No. 2012-232591 SUMMARY OF THE INVENTION Problems to be Solved by the Invention
On the basis of these circumstances, the present invention relates to a polymer substrate with hard coating layer obtained by laminating a high hardness hard coating layer by plasma-enhanced chemical vapor deposition (PE-CVD) on a surface layer, and an object thereof is to obtain a composition capable of realizing the three characteristics consisting of a high level of abrasion resistance comparable to that of inorganic glass, superior boiling water resistance as a typical property of environmental resistance (including an “elapsed result” for adhesion), and superior heat resistance. Means for Solving the Problems
As a result of conducting extensive studies, the inventors of the present invention found that the aforementioned problems can be solved by satisfying the requirements that film thickness of a silicon oxide film obtained by PE-CVD, nanoindentation depth and critical compression ratio be within prescribed ranges in a polymer substrate having a hard coating layer, thereby leading to completion of the present invention.
In order to satisfy the aforementioned requirements, in addition to the film thickness of a silicon oxide film obtained by PE-CVD, mechanical properties and chemical properties being within prescribed ranges, it is also necessary to increase as much as possible adhesive strength between the silicon oxide layer obtained by PE-CVD and a cured underlayer serving as the foundation thereof, and this is realized according to the means described below.
The cured underlayer is a layer composed of inorganic oxide fine particles having a primary particle diameter of 1 nm to 200 nm and a hydrolysis-condensation product of a silicon compound, and the cured underlayer is formed after having adjusted the rate of progression (degree of aging) of the hydrolytic condensation reaction of a precursor material composition thereof to be within a proper range.
Plasma bombardment treatment is performed prior to forming the silicon oxide layer by PE-CVD so that surface properties of the cured underlayer are within a prescribed range.
The silicon oxide layer is formed by PE-CVD in the vicinity of the interface with the cured underlayer (initial growth process) within the range of a low deposition rate.
These three means make it possible to greatly improve interlayer adhesive strength between the silicon oxide layer obtained by PE-CVD and the cured underlayer as well as realize the objects of the invention of the present application in the form of abrasion resistance, environmental resistance (boiling water resistance (elapsed adhesion)) and heat resistance.
Namely, the present invention is as described below with respect to solving the aforementioned problems.
A polymer substrate with hard coating layer comprising a polymer substrate having a thickness of 1 mm to 20 mm and a hard coating layer on the surface thereof; wherein,
the hard coating layer comprises:
a cured underlayer laminated on the surface of the polymer substrate, containing as a main component thereof a hydrolysis-condensation product of an organic silicon compound, and having a thickness of 0.1 μm to 20 μm, and
a silicon oxide layer that makes direct contact with the cured underlayer on the opposite side from the polymer substrate, is formed by PE-CVD using an organic silicon compound as raw material, and satisfies all of the following requirements (a) to (c):
(a) film thickness of the silicon oxide layer is within the range of 3.5 μm to 9.0 μm,
(b) maximum indentation depth of the surface of the silicon oxide layer, as determined by measuring nanoindentation under conditions of a maximum load of 1 mN, is 150 nm or less, and
(c) the value of critical compression ratio K of the silicon oxide layer, as defined by formula
in a 3-point bending test of the polymer substrate with hard coating layer that imparts indentation displacement in which the surface laminated with the silicon oxide layer becomes concave, is 0.975 or less: K =( R−D/ 2)/ R −(0.00215× d ) R =(( G/ 2).sup.2−(δ L ).sup.2)/(2×δ L ) Formula
(wherein,
D represents the total thickness (mm) of the polymer substrate with hard coating layer,
d represents the film thickness (μm) of the silicon oxide layer,
G represents the distance (mm) between two end fulcrum points in a 3-point bending tester,
δL represents indentation displacement (mm), measured when the silicon oxide layer begins to separate from a cut line (separation starting line) drawn in advance at the location of the central fulcrum point where a weight is applied in a 3-point bending test, and
R represents the bend radius (mm) of the polymer substrate with hard coating layer, measured when the silicon oxide layer begins to separate from a cut line (separation starting line) drawn in advance at the location of the central fulcrum point where a weight is applied in a 3-point bending test).
The polymer substrate with hard coating layer described in
above, wherein the ratio of infrared absorbance of the silicon oxide layer at a wave number of 930 cm.sup.−1 to that at a wave number of 1020 cm.sup.−1 (α.sub.930/α.sub.1020) is 0.30 or less.
The polymer substrate with hard coating layer described in
or
above, wherein the ratio of infrared absorbance of the silicon oxide layer at a wave number of 1280 cm.sup.−1 to that at a wave number of 1020 cm.sup.−1 (α.sub.1280/α.sub.1020) is within the range of 0.002 to 0.020.
The polymer substrate with hard coating layer described in any of
to
above, wherein indentation hardness of the surface of the silicon oxide layer as determined by measuring nanoindentation under conditions of a maximum load of 1 mN is 3 GPa or more.
The polymer substrate with hard coating layer described in any of
to
above, wherein surface roughness (Ra) of the silicon oxide layer when measured using the dynamic force mode (DFM) of a scanning probe microscope under conditions of observing by 5.0 μm square is 5.0 nm or less.
The polymer substrate with hard coating layer described in any of
to
above, wherein an adhesive layer containing an acrylic resin composition as a main component thereof and having a film thickness of 0.1 μm to 20 μm is interposed between the polymer substrate and the cured underlayer.
A method for producing the polymer substrate with hard coating layer described in any of
to
above, comprising: forming the cured underlayer by coating a precursor material composition, in which the degree of aging (Ag) as represented by the following formula has a value within the range of 0.80 to 0.85, on the polymer substrate followed by drying and heat curing: Ag={([X]+2×[Y]+3×[Z])/[S]}/3 (wherein,
with respect to the chemical shifts of silicon atoms of a hydrolysis-condensation product of the organic silicon compound, which is measured when a silicon atom of tetramethylsilane is assigned a value of 0 ppm after measuring the silicon nuclear magnetic resonance spectrum (.sup.29Si-NMR) using heavy water for the solvent under conditions consisting of an observation frequency of 79 MHz, observation pulse of 6.0 μs, repetition time of 30 seconds and broadening factor of 5 Hz,
the integration value of all peaks within the range of −45.0 ppm to −70.0 ppm is defined as [S], and,
within that peak integration value,
the peak integration value within the range of −45.0 ppm to −52.5 ppm is defined as [X],
the peak integration value within the range of −52.5 ppm to −61.0 ppm is defined as [Y], and
the peak integration value within the range of −61.0 ppm to −70.0 ppm is defined as [Z].
A method for producing the polymer substrate with hard coating layer described in any of
to
above, comprising: adjusting the surface of the cured underlayer so that the ratio of infrared absorbance at a wave number 1065 cm.sup.−1 to that at a wave number of 1020 cm.sup.−1 (α.sub.1065/α.sub.1020) is within the range of 0.75 to 0.87, prior to laminating the silicon oxide layer by PE-CVD.
A method for producing the polymer substrate with hard coating layer described in any of
to
above, comprising: adjusting the surface of the cured underlayer so that surface roughness (Ra) in the case of having measured with the dynamic force mode (DFM) of a scanning probe microscope under conditions of observing by 5 μm square is within the range of 0.7 nm to 10.0 nm, prior to laminating the silicon oxide layer by PE-CVD.
The method for producing a polymer substrate with hard coating layer described in
or
above, wherein adjustment of the surface of the cured underlayer is carried out by plasma excitation or by colliding ionized inert gas with the surface of the cured underlayer.
A method for producing the polymer substrate with hard coating layer described in any of
to
above, wherein the silicon oxide layer is formed at an average deposition rate (nm/sec) between the start of deposition and 30 seconds thereafter of deposition of 1 nm/sec or less. Effects of the Invention
According to the present invention, since a polymer substrate with hard coating layer can be obtained that is provided with a high level of abrasion resistance comparable to that of inorganic glass and the like, the ability to withstand harsh environmental conditions corresponding to outdoor use (boiling water resistance (elapsed adhesion)) and heat resistance, it can be used in a wide range of applications as a high-performance resin glazing material for use in automobile window glass and the like.
FIG. 1 is a schematic diagram of one example of a capacitive coupling type of PE-CVD device able to be used to form the silicon oxide layer of the present invention by PE-CVD.
FIG. 2 is a schematic diagram of another example of a capacitive coupling type of PE-CVD device able to be used to form the silicon oxide layer of the present invention by PE-CVD.
FIG. 3 shows an example of a reactive gas introducing head provided on an electrode in a capacitive coupling type of PE-CVD device able to form the silicon oxide layer of the present invention by PE-CVD, with (a) depicting a horizontal cross-sectional view and (b) indicating the arrangement (example) of a large number of gas blowout holes provided in a surface on the side opposing a treated substrate.
FIG. 4 is a cross-sectional schematic diagram of a polymer substrate with hard coating layer applied in one embodiment of the present invention.
FIG. 5 is a cross-sectional schematic diagram of a polymer substrate with hard coating layer applied in another embodiment of the present invention.
FIG. 6 is a schematic diagram of a 3-point bending test (sample placement stage, prior to generation of bending displacement) carried out on the polymer substrate with hard coating layer of the present invention.
FIG. 7 is a schematic diagram of a 3-point bending test (test in progress, during generation of bending displacement) carried out on the polymer substrate with hard coating layer of the present invention.
FIG. 8 is a diagram for explaining a cut line (separation starting line) of a 3-point bending test.
FIG. 9 is an explanatory drawing relating to calculation of critical compression ratio from the results of a 3-point bending test.
Although the polymer substrate with hard coating layer according to the present invention has for an essential requirement thereof the presence of a hard coating layer in which a cured underlayer and silicon oxide layer obtained by PE-CVD are laminated in that order on a polymer substrate, other layers can be laminated as necessary.
In practical terms, a configuration is frequently used comprising interposing an adhesive layer between the polymer substrate and the cured underlayer. One example thereof is a polymer substrate with hard coating layer having a configuration in which an adhesive layer 60 and a cured underlayer 70 are laminated in that order on both sides of a polymer substrate 50 , and a silicon oxide layer 80 obtained by PE-CVD is laminated in that order as shown in the cross-sectional schematic diagram of FIG. 4 . In addition, another example thereof is a polymer substrate with hard coating layer having a configuration in which an adhesive layer 60 , a cured underlayer 70 and a silicon oxide layer 80 obtained by PE-CVD are laminated in that order on both sides of a polymer substrate 50 as shown in the cross-sectional schematic diagram of FIG. 5 . Furthermore, the laminar configuration of the polymer substrate with hard coating layer according to the present invention is not limited to these examples.
Furthermore, in the present invention, although it is an essential requirement that the cured underlayer 70 and the silicon oxide layer 80 obtained by PE-CVD be laminated in that order on at least one side of the polymer substrate 50 , the adhesive layer 60 and laminated layers on the other side are not necessarily required, and a preferable configuration is selected corresponding to the application and need. For example, the lamination and formation of a layer other than the adhesive layer 60 , the cured underlayer 70 and the silicon oxide layer 80 obtained by PE-CVD (such as an ultraviolet-curable resin layer) on the other side can also be selected.
The following provides a sequential detailed explanation of each component that composes the polymer substrate with hard coating layer according to the present invention and methods for adjusting each component.
<Polymer Substrate 50 >
Examples of materials of the polymer substrate 50 include polycarbonate resin, acrylic resin such as polymethyl methacrylate, polyester resin such as polyethylene terephthalate, polybutylene terephthalate or poly(ethylene-2,6-naphthalate), polystyrene resin, polypropylene resin, polyarylate resin, polyethersulfone resin, ABS resin and polylactic acid resin. These resins can be used alone or two or more types can be used as a mixture. Among these, polycarbonate resin having superior transparency, heat resistance and impact resistance is particularly preferable in the case of considering use in automobile window applications.
Furthermore, with respect to resin heat resistance, the heat distortion temperature (HDT) is preferably 100° C. or higher, more preferably 120° C. or higher and even more preferably 130° C. or higher.
One example of a polycarbonate resin is a polycarbonate resin obtained by reacting a divalent phenol and a carbonate precursor by an interfacial polycondensation method or a fusion method. Typical examples of divalent phenols include 2,2-bis(4-hydroxyphenyl)propane (commonly referred to as bisphenol A), 2,2-bis(3-methyl-4-hydroxyphenyl)propane, 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl)ethane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)-3-methylbutane, 9,9-bis{(4-hydroxy-3-methyl)phenyl}fluorene, 2,2-bis(4-hydroxyphenyl)-3,3-dimethylbutane, 2,2-bis(4-hydroxyphenyl)-4-methylpentane, d1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane and α,α-bis(4-hydroxyphenyl)-m-diisopropylbenzene, bis(4-hydroxyphenyl)sulfide and bis(4-hydroxyphenyl)sulfone, and among these, bisphenol A is preferable. These divalent phenols can be used alone or two or more types can be used as a mixture.
In addition, a carbonyl halide, carbonate ester or haloformate and the like is used for the carbonate precursor, and specific examples thereof include phosgene, diphenyl carbonate and dihaloformates of divalent phenols.
In the production of a polycarbonate resin by reacting a divalent phenol and carbonate precursor by an interfacial polycondensation method or fusion method, a catalyst, chain-end terminator or antioxidant of a divalent phenol may be used as necessary. In addition, the polycarbonate resin may be a branched polycarbonate resin obtained by copolymerizing a polyfunctional aromatic compound having three or more functional groups, or may be a mixture obtained by mixing two or more types of the resulting polycarbonate resins.
The molecular weight of the polycarbonate resin in terms of the viscosity-average molecular weight (M) is preferably 10,000 to 50,000 and more preferably 15,000 to 35,000. A polycarbonate resin having this viscosity-average molecular weight allows the obtaining of adequate strength and demonstrates favorable melt fluidity during molding, thereby making this preferable.
Viscosity-average molecular weight as referred to in the present invention is determined by substituting specific viscosity (η.sub.sp), which is determined from a solution obtained by dissolving 0.7 g of polycarbonate resin in 100 ml of methylene chloride at 20° C., into the formula indicated below. η.sub.sp /c =[η]+0.45×[η].sup.2 c (where, [η] represents limiting viscosity) [η]=1.23×10.sup.−4 M.sup.0.83 c= 0.7
In addition, other preferable examples of polycarbonate resins include polycarbonate resin obtained by copolymerization of isosorbide and an aliphatic diol, and various types of copolymerized polycarbonates such as polycarbonate-polyorganosiloxane copolymers.
The polycarbonate resin can be used after adding and mixing therein a stabilizer such as a phosphite ester or phosphonate ester, a flame retardant such as tetrabromobisphenol A, a low molecular weight polycarbonate of tetrabromobisphenol A or decabromodiphenol, an organic ultraviolet absorber such as a benzotriazole, benzophenone, triazine or salicylate, an inorganic ultraviolet absorber such as titanium oxide, cerium oxide or zinc oxide, an ultraviolet shielding agent such as a cyanine-based compound, squarylium-based compound, thiol-nickel complex salt-based compound, phthalocyanine-based compound, triallylmethane-based compound, naphthoquinone-based compound, anthraquinone-based compound, carbon black, antimony oxide, tin oxide doped with indium oxide or lanthanum boride, a colorant or a lubricant as necessary.
Furthermore, the thickness of the polymer substrate is preferably within the range of 1 mm to 20 mm. If the thickness is less than 1 mm, it becomes difficult to retain mechanical strength required by an automobile window and the like, flexural deformation of the substrate increases accompanying lamination of the silicon oxide layer by PE-CVD, and there are many cases in which problems with dimensional stability and appearance occur, thereby making this undesirable. On the other hand, if the thickness exceeds 20 mm, it becomes difficult to retain surface smoothness necessary for a window material and obtain a molded substrate having a low level of optical distortion (such as perspective distortion) while also increasing the substrate weight, thereby making this undesirable.
The thickness of the polymer substrate is more preferably 2 mm to 10 mm and even more preferably 3 mm to 7 mm.
<Adhesive Layer 60 >
An adhesive layer that fulfills the role of enhancing the adhesive strength of the polymer substrate and cured underlayer is preferably provided as necessary by interposing between the polymer substrate and the cured underlayer having as a main component thereof a hydrolysis-condensation product of an organic silicon compound.
Examples of methods used to form the adhesive layer include a method consisting of wet-coating onto the polymer substrate, a lamination method, insert molding, two-color molding, melt lamination and melt pressing.
Although various types of resins or resin compositions are used for the adhesive layer, it is particularly preferably a layer containing an acrylic resin composition as a main component thereof. Here, one type of a mixture of a plurality of types of acrylic resins among those represented by the following general formula (A), (A-1), (A-2), (A-3) or (A-4) and/or an acrylic copolymer resin containing 70 mol % or more of a plurality of repeating units of acrylic resins represented by (A-1), (A-2), (A-3) or (A-4) (to be collectively referred to as Component A) are used preferably. Moreover, a copolymer resin composed of 1 mol % to 98 mol % of unit (A-1), 1 mol % to 85 mol % of unit (A-2), 1 mol % to 15 mol % of unit (A-3) and 0 mol % to 15 mol % of unit (A-4) is preferably used for the acrylic copolymer resin, and other unit structures can also be introduced into the copolymer as necessary.
In the above formula, X represents a hydrogen atom or methyl group, the percentage of hydrogen atoms in X is 30 mol % or less, Y represents a methyl group, ethyl group, cycloalkyl group, hydroxyalkyl group having 2 to 5 carbon atoms or group containing an ultraviolet ray-absorbing moiety, the total percentage of methyl groups and ethyl groups in Y is within the range of 1 mol % to 98 mol %, the percentage of cycloalkyl groups is within the range of 0 mol % to 85 mol %, and the percentage of groups containing an ultraviolet ray-absorbing moiety is within the range of 0 mol % to 15 mol %.
In the above formula, Y.sup.1 represents a methyl group or ethyl group, there are no particular restrictions on the percentages of methyl groups and ethyl groups, and can be used at a molar ratio of 0:100 to 100:0.
In the above formula, X1 represents a hydrogen atom or methyl group, Y.sup.2 represents a cycloalkyl group, and the number of carbon atoms of the cycloalkyl group is preferably 5 to 12.
Unit (A-2) can be introduced by copolymerizing a monomer exemplified below. Examples of monomers include cyclohexyl acrylate, 4-methylcyclohexyl acrylate, 2,4-dimethylcyclohexyl acrylate, 2,4,6-trimethylcyclohexyl acrylate, 4-t-butylcyclohexyl acrylate, adamantyl acrylate, dicyclopentadienyl acrylate, cyclohexyl methacrylate, 4-methylcyclohexyl methacrylate, 2,4-dimethylcyclohexyl methacrylate, 2,4,6-trimethylcyclohexyl methacrylate, 4-t-butylcyclohexyl methacrylate, adamantyl methacrylate, dicyclopentadienyl methacrylate, cyclohexylmethyl methacrylate, 4-methylcyclohexylmethyl methacrylate, 2,4-dimethylcyclohexylmethyl methacrylate, 2,4,6-trimethylcyclohexylmethyl methacrylate and 4-t-butylcyclohexylmethyl methacrylate, and cyclohexyl methacrylate is used particularly preferably.
In the above formula, X.sup.2 represents a hydrogen atom or methyl group, Y.sup.3 represents an alkylene group having 2 to 5 carbon atoms, and examples of alkylene groups include an ethylene group, trimethylene group and tetramethylene group.
Unit (A-3) can be introduced by copolymerizing a monomer exemplified below. Examples of monomers include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate, 3-hydroxybutyl acrylate, 3-hydroxybutyl methacrylate, 2-hydroxybutyl acrylate and 2-hydroxybutyl methacrylate, and among these, 2-hydroxyethyl methacrylate is used preferably.
In the above formula, X.sup.3 represents a hydrogen atom or methyl group, and Y.sup.4 represents an ultraviolet absorber residue and preferably a triazine-based ultraviolet absorber residue. Unit (A-4) can be introduced by copolymerizing an acrylate or methacrylate monomer having an ultraviolet absorber residue. More specifically, a repeating unit derived from an acrylate monomer represented by the following formula (A-4-a) or formula (A-4-b) is preferably used as an acrylate or methacrylate monomer having an ultraviolet absorber residue.
In the above formula, R.sup.11 represents an alkylene group having 2 to 6 carbon atoms, R.sup.12 represents a hydrogen atom, alkyl group having 1 to 18 carbon atoms or alkoxy group having 1 to 18 carbon atoms, R.sup.13 and R.sup.14 may be the same or mutually and independently represent a hydrogen atom, halogen atom, alkyl group having 1 to 18 carbon atoms, alkoxy group having 1 to 18 carbon atoms or phenyl group optionally substituted with an alkyl group having 1 to 18 carbon atoms or a halogen atom, R.sup.15 represents an alkyl group having 1 to 18 carbon atoms, X.sup.4 represents a hydrogen atom or methyl group, and V.sup.1 represents a hydrogen atom, OH group or alkyl group having 1 to 12 carbon atoms.
In the above formula, R.sup.16 represents a hydrogen atom, alkyl group having 1 to 18 carbon atoms or alkoxy group having 1 to 18 carbon atoms, R.sup.17 and R.sup.18 are the same or mutually and independently represent a hydrogen atom, alkyl group having 1 to 18 carbon atoms, alkoxy group having 1 to 18 carbon atoms, or phenyl group optionally substituted with an alkyl group having 1 to 18 carbon atoms or a halogen atom, R.sup.19 represents an alkyl group having 1 to 18 carbon atoms, X.sup.5 represents a hydrogen atom or methyl group, and V.sup.2 represents a hydrogen atom, OH group or alkyl group having 1 to 12 carbon atoms.
An ultraviolet absorber residue refers to a residue of an ultraviolet absorber that has ultraviolet absorption performance. For example, since a triazine-based ultraviolet absorber residue is missing a portion of the end of a triazine compound and is bound to an acrylic copolymer, strictly speaking, there is a difference in molecular weight between the residue and the triazine compound. However, since the amount that is missing is extremely small in comparison with the total, the weight of the residue and the weight of the triazine compound are considered to be equal for the sake of convenience in the present invention.
In the case of using as a copolymer, a repeating unit represented by the following formula (A-5) is preferably contained. Containing unit (A-5) makes it possible to improve weather resistance by imparting radical scavenging ability.
In the above formula, R.sup.10 represents a hydrogen atom or alkyl or alkoxy group having 1 to 14 carbon atoms.
R.sup.10 preferably represents an alkyl group or alkoxy group having 1 to 8 carbon atoms. Specific examples thereof include a methyl group, ethyl group, propyl group, butyl group, methoxy group, ethoxy group, propoxy group and butoxy group.
The percentage at which unit (A-5) is contained is preferably 1 mol % to 15 mol %, more preferably 0.1 mol % to 10 mol % and even more preferably 1 mol % to 8 mol % based on a value of 100 mol % for all repeating units of the acrylic copolymer.
(Other Repeating Units)
In the case of using a copolymer, other repeating units may also be contained for the purpose of improving adhesion, weather resistance and heat resistance or imparting functionality and the like. The amount of the other repeating unit is 30 mol % or less, preferably 20 mol % or less and particularly preferably 10 mol % or less based on a value of 100 mol % for all repeating units of the acrylic copolymer.
Other repeating units can be introduced by copolymerizing a vinyl monomer capable of copolymerizing with an acrylate or methacrylate monomer. Examples of other vinyl monomers include acrylic acid, methacrylic acid, methacrylamide, methyl acrylate, ethyl acrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, dodecyl acrylate, dodecyl methacrylate, 2-(2′-hydroxy-5′-acryloxyethylphenyl)benzotriazole, 2-(2′-hydroxy-5′-acryloxyethoxyphenyl)benzotriazole, 2-(2′-hydroxy-5′-acryloxypropylphenyl)benzotriazole, 2-(2′-hydroxy-5′-acryloxypropoxyphenyl)benzotriazole, 2-(2′-hydroxy-5′-acryloxyethylhenyl)-5-chlorobenzotriazole, 2-(2′-hydroxy-3′-acryloxyethyl-5′-t-butylphenyl)benzotriazole,2-(2′-hydroxy-3′-acryloxyethyl-5′-b-butylphenyl)-5-chlorobenzotriazole, 2-hydroxy-4-(acryloxyethoxy)benzophenone, 2-hydroxy-4-(acryloxypropoxy)benzophenone, 2,2′-dihydroxy-4-(acryloxyethoxy)benzophenone, 2-hydroxy-4-(acryloyloxyethyl)benzophenone, 2-(2′-hydroxy-5′-methacryloxyethylphenyl)benzotriazole, 2-(2′-hydroxy-5′-methacryloxyethoxyphenyl)benzotriazole, 2-(2′-hydroxy-5′-methacryloxypropylphenyl)benzotriazole, 2-(2′-hydroxy-5′-methacryloxypropoxyphenyl)benzotriazole, 2-(2′-hydroxy-5′-methacryloxyethylphenyl)-5-chlorobenzotriazole, 2-(2′-hydroxy-3′-methacryloxyethyl-5′-t-butylphenyl)benzotriazole, 2-(2′-hydroxy-3′-methacryloxyethyl-5′-t-butylphenyl)-5-chlorobenzotriazole, 2-hydroxy-4-(methacryloxyethoxy)benzophenone, 2-hydroxy-4-(methacryloxypropoxy)benzophenone, 2,2′-dihydroxy-4-(methacryloxyethoxy)benzophenone and 2-hydroxy-4-(methacryloyloxyethyl)benzophenone.
The description continues in the full USPTO document.
About 6,026 words. The USPTO PDF has it with every drawing.
Fees are due 3.5, 7.5 and 11.5 years after grant. This patent expired on September 12, 2025, so the fee marked "not paid" was the one that went unpaid.
POLYMER SUBSTRATE WITH HARD COAT LAYER AND MANUFACTURING METHOD FOR SUCH POLYMER SUBSTRATE
Filed Mar 2015 · published Apr 2017Polymer substrate with hard coat layer and manufacturing method for such polymer substrate
Filed Mar 2015 · granted Sep 2017Earlier publications, parents and continuations. None of them can still be enforced, or this patent would not be listed.
Prior art cited by the examiner or applicant. Useful when you check your own idea for novelty.
Everything on this page comes from the documents linked above.
